Download latest nightly image

FCOS nightly images are built using Jenkins pipleine in CentOS CI . Download latest ISO or qcow2 nightly image which you like.

While writing this blog latest nightly ISO image name is fedora-coreos-30.113-installer.iso and qcow2 image name is fedora-coreos-30.113-installer.iso . I will be using these names in this blog but when you try replace it with the media name which you downloaded.

Ignition Config

Similar to Container Linux, FCOS also requires ignition config to perform initial configuration during first boot. We will create fcos.ign ignition config file which defines to create a user test with password test, authorized ssh key and adding user test to wheel group to provide sudo access.

On login prompt, enter test as user name and test as password as we added in the ignition config and you should be inside a FCOS system!

Installing and Running ISO image

ISO image fedora-coreos-30.113-installer.iso contains initramfs.img and vmlinuz to boot the kernel. We will also need fedora-coreos-30.113-metal-bios.raw.gz or fedora-coreos-30.113-metal-bios.raw.gz from latest nightly repo depending upon what kind of installation you want. For our example, we will download fedora-coreos-30.113-metal-bios.raw.gz image. Installer will need metal-bios image and ignition config during the install process which we will pass as kernel command args. Let’s host fedora-coreos-30.113-metal-bios.raw.gz and fcos.ign files locally.

When ISO boots, in grub menu use <TAB> to add additional args in kernel command line . They are coreos.inst.install_dev (installation device), coreos.inst.image_url (installer image url) and coreos.inst.ignition_url (ignition config url). It looks something like below:

Once, additional parameter is added press <ENTER> to continue the installation. Once installation completes successfully and vm reboots, it will prompt for user login which will be same as we mentioned in running qcow section.